1. Field of the Invention
The present invention relates to a ball chain and a method of manufacturing the same, wherein the ball chain is provided by hollow metal balls connected in a chain-like manner by connecting shafts, each of the connecting shafts having connecting heads on both end portions.
2. Description of Related Art
FIG. 5 is a partly cross-sectional view of a conventional ball chain shown as a broken portion.
A conventional ball chain 31 has a plurality of hollow metal balls 32 and is provided by connecting connecting shafts 33 in a chain-like manner, each of the connecting shafts 33 having connecting heads 33a on both end portions, as shown in FIG. 5.
Each of the metal balls 32 is provided by rounding a piece of metal to form a shape of a hollow sphere and has a butt seam 34 of the metal piece.
At the upper and lower end portions the butt seam 34, apertures are provided.
Through each aperture a shaft portion of the connecting shaft 33 is inserted, and the connecting heads 33a on both ends of the connecting shaft 33 are formed bulged to have a larger diameter than the inner diameter of the aperture.
The connecting heads 33a of the connecting shaft 33 and the apertures of the metal balls 32 are engaged so that the connecting shaft 33 cannot come off the aperture.
By continuously forming such structure, each of the metal balls 32 are connected by the connecting shafts 33 in a chain-like manner.